Magnetic separating apparatus



(No Model.)

0. E. FRITZ. Magnetic Separating Apparatus.

N. PETERS. PH

Hllll mm llllll llllll Patented Oct. 5, I880.

OTO-LITHOGRAPHER smNGT N u c CHARLES E. FRITZ, OF

ONEONTA, NEWV YORK.

MAGNETIC SEPARATING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 232,956, dated October 5, 1880. Application filed May 12, 1880. (No model.)

To all whom it may concern:

Be it known that I, CHARLES E. FRITZ, a citizen of the United States, residing at Oneonta, Otsego county, State of New York, have invented certain new and useful Improvements in Separating Ironor other Magnetic Metals from Grain or other N on-Magnetic Substances 5 and I do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same.

The invention relates, principally, to magnetic grain-separators of that class which have a diaph agm or screen placed before the magnet or magnets for preventing actual contact of the iron with the magnets while utilizing their attractive powers through it.

It consists in arranging the magnets and their diaphragm or sheath in sections or parts, and, instead of the magnets being in one body and the diaphragm in one piece, the magnets are arranged in any desired number of series or lots, and each lot of magnets has its own part or sectional diaphragm or sheath, each section being movable independently of the others, as hereinafter explained.

It also consists in constructing and using the diaphragm in the form of sheaths whereby from two to five or more times as much of the attractive power of the magnets is utilized as has heretofore been practicable, the remainder having previously been entirely useless, and therefore wasted.

It also consists in arranging these sheaths and their magnets, not fixed together, as heretofore practiced, with diaphragms, (at least during use,) but making them independent of each other, so that either or both may move or remain stationary or be manipulated in any manner preferred, independently of the other or others, during the operation of the machine and as a part of that operation.

It further consists in using the sheath or sheaths as carriers, to remove the iron from the vicinity of the magnets far enough to carry it beyond their attraction-4'. 0., beyond the magnetic fieldwhen it will cease to be attracted, and can be thrown oft or discharged, thus entirely cleaning a m agnet or series of magnets at one motion, and saving the time, trouble, and annoyance of brushing or picking off the pieces by hand. This carriage or motion may be either automatic or manual.

Other improvements are fully set forth in the specification and claims.

Heretofore the magnets have been arranged with their poles pointing outward and a diaphragm or plate of non-magnetic metal placed over the extremities of the poles. The material to be separated was then brought as near as possible to the n1agnets,-whicli would attract the iron therefrom and hold it in contact with the diaphragm, from which it would be brushed or removed at intervals by brushes or any convenient means.

The use of diaphragms is very convenient, especially with permanent magnets, as it allows of arranging the magnets in manners or places where it would be difficult, if notimpossible, to clean the magnets if the iron were suffered to adhere directly to them. They are also very useful in connection with electromagnets or temporary or induced magnets of any kind when there is any danger of residual magnetism or similar causes interfering with the release and discharge of the iron gathered by the magnets while active; or where the material to be cleaned contains magnetized substances, which, by virtue of their own magnetism, would adhere to the magnets or magnetized pieces even after the temporary magnetism of the latter had been wholly removed.

Another advantage of diaphragms is that when not in use iron can be thickly strewn over them, to act as keepers for the magnets and preserve their strength. When Wanted for use, the whole of the iron can be lifted off at once and discharged without requiring a long and tedious cleaning operation to prepare them for use. The loss of magnetic power by removing the keepers is less in this way than when the magnets and the keepers come in actual contact, and the magnets will last longer; but, the diaphragms being placed over the extremities of the poles of the magnets, only one attracting-surface of each branch of the magnet was utilized-the end.

As bar-magnets are seldom or never used for separating purposes, they are not meant in this description, which only refers to magnets which utilize both ends; but, of course,

these sheaths may be applied to them with the same advantage as to'the others.

To remedy this great waste or loss thus sustained I. mold or form the diaphragm so as to embrace or surround the magnets more or less, and such diaphragms I term sheaths. By forming the diaphragm to fit not only the two ends of the magnets, but also two of the sides, I utilize twice as many surfaces as the ordinary diaphragm, as is shown in Fig. 1, where A is the magnet, and D the diaphragm, which may be arranged in steps or stages, with the magnets touching it in either of the ways depicted, or otherwise. This arrangement utilizes four of the surfaces of the magnet, and may be applied to a trough, revolving cylinder,.or any form of conveyer preferred. Another advance is madeby forming the sheath in the shape of a trough, into which the branches of the magnet are set, fitting the end and two sides of each branch, or six surfaces in all.

By making a pocket or bag sheath for each magnet, as in Fig. 2, I utilize eight surfaces, and by forming an individual sheath surrounding each branch of the magnet I utilize the whole of its ten attracting-surfaces, as shown in Fig. 3. This is the form I prefer. The sheaths may, of course, reach as far up the branches as the surfaces may require to be utilized. It will therefore be'understood that by a sheath I mean a diaphragm which is formed to lit the magnet not only on the end ofthe branch, butalso atleastoneof the sidesthat is tosay, it should fit at least two of the attracting-surfaces, instead of one, as heretofore. If the ends of the magnets are not utilized for attracting purposes, then I mean by sheath a shield or casing which will permit of utilizing one or more of the sides of the magnets for attracting iron without permitting actual contact of the iron with the magnets; and, to avoid repetition of the substances or materials which may be separated, either in this description or in the claims, I would say that when speaking of iron or iron fragments I mean pieces of all kinds of magnetic substances which it may be required to separate from other or non-magnetic substances, whether the iron, 850., be magnetized or not. So, in speaking of grain, I mean, also, all other non-magnetic substances, whether metallic or otherwise.

Either permanent or temporary magnets may be used; but this invention is especially adapted for the former. Any required number may be used, and they may be of any suitable form; but for ordinary use I prefer the modified form of horseshoe-magnets having parallel branches, and known as machinemagnets. For special uses, however, they may be of any form preferred.

Fig. 4 shows a curved form of magnet made from a semicircular strip of steel bent in the middle and subtendin g an angle of about ninety degrees. Thisformis especially adapted for separating the magnets and their sheaths by rotation about a pivot at the center of the are or curve of the magnet. The sheath may be taken off and put on the magnet, or the magnets moved out and into the sheaths. The magnets are attached to the proper portion of the trough, cylinder, or other conveyer, and secured by bolts or in any suitable manner to hold them firmly in their proper positions.

Fig. 5 shows the arrangement of permanent magnets in a trough-separator for a very large trough, which will clean from five thousand to fifteen thousand bushels of grain per day. The signs and indicate the different poles. Any other suitable arrangement may be used; but that shown is probably as good as any, as it does not obstruct the flow of the grain too much, and gives every assurance that all the iron will be extracted. Of course, in a trough for an ordinary mill fewer magnets may be used. The inclination of the trough should be such as to feed the grain through properly, and depends on the quantity of grain to be passed and the obstruction caused by the magnets, which latter will beincreasedit' the magnets are placed zigzag in the trough, as many recommend. The inclination of the trough must be increased till the grain flows freely in each case, all of which the operator can regulate for himself, as usual.

Diaphragms are made usually of non-magnetic metal, such as zinc or brass. They may also be of any other suitable material, of which papier-mach, paper treated or hardened by chloride of zinc or otherwise, leather, wood, rubber, either hard or soft, 850., may be mentioned. I do not confine myself to any such materials, however, but also make them of a magnetic metal, provided they be not permanently magnetized, so that they will cease to attract'the iron when they are removed from the magnetic field, and will let it drop off freely into a trough or other suitable receptacle. When the diaphragm is of such material its thickness is of less consequence, as it becomes temporarily a magnet itself when the magnet is behind it; but a non-magnetic diaphragm should be as thin as permissible, as the nearer the grain can approach to the magnets the greater their power to separate theiron from it. The sheaths must, of course, fit as closely to the magnets as may be without interfering with their ready removal and replacement, and the joints in them, if any, should be tight enough to exclude all particles of iron.

In using magnetic diaphragms or sheaths it would be difficult to remove them from contact with the magnets without considerable force, and perhaps liability to injury. I obviate this, however, by interposing a layer of non-magnetic material between the magnet and diaphragm, to prevent actual contact between the two magnetic materials. This may be of any suitable substance which will be thin but lasting, and may be applied either to the exterior of the magnet or the interior -walls, preferably the latter.

of the diaphragm or sheath, or it may be separate from both. Such a non-magnetic layer or coating may also be applied on the outside of the diaphragm or sheath, and would be beneficial in several ways. As an example of this variety of diaphragms or sheaths, they may be made of common tin-plate, being composed of soft iron plated on both sides with tin. Other materials may be used for plating or coating diaphragms on one or both sides With a nonmagnetic metal or substance.

When using magnetifidiaphragms it is found thatif all the iron is soft it is readily discharged from them. But the grain often contains magnetized fragments of metal. These adhere to the diaphragms by their own magnetism, even after the diaphragms have ceased to be magnetized, and require to be brushed or picked off by hand or by any suitable means. I separate such magnetized fragments from the grain separately from the unmagnetized pieces by arranging one or more gangs of soft-iron bars, a, Fig. 5, having the form of magnets, at the top of the trough, to which they adhere, leaving the unmagnetized parts to flow on down and be caught by the real magnets, as before described. For convenience of cleaning, these bars or pseudoanagnets may have non-magnetic sheaths.

The sheaths shown in Figs. l and 2 may be formed by simply corrugating sheets of material in the proper form or in any other suitable manner, while those shown in Fig. 3 can be made by stamping out pieces from sheets, and then bending them up orjoining them in the proper form. Fig. 6 shows a sheath for a single branch of an ordinary machine-magnet, the right being a top view, showing the four sides with a lateral flange extending out on each side, while at the left is a longitudinal transverse section, showing the bottom or end, two sides, and the two side flanges. The end may be either inside or outside of the side If necessary to strengthen the flanges, they may be soldered to or supported by a rectangular piece, as shown by the dotted lines, suitably perforated at the center.

The sides of the sheaths maybe brought together in many different ways, some of which are shown in Fig. 7, making either a lap or splicejoint. The front edge, where the principal part of the friction from the grain comes on the sheath, may have two or more thicknesses of metal, and be bent together in various forms, as shown, except that the metal in all cases comes firmly together, although shown apart in the drawings for the sake of showing its various parts and joints more clearly. Another object in having the front edges of the sheaths thicker than the rear ones is to lessen the attraction for the iron in front and prevent its accumulation there, but dispose it to be drawn around in the rear and held, where it obstructs the flow of the grain less. By means of suitable dies these sheaths can be formed very cheaply and of uniform size. The magnets should also be made of uniform sizes.

The whole sheath With its flange may be drawn up in proper shape without seam, similarly to the cheap pencil-cases and many other articles of commerce, or they may be cast or molded entire of suitable material. Even clastic rubber sheaths stretched over the poles may be used, and will last much longer than would be supposed.

Fig. 8 shows one way of combining the magnets with individual sheaths in a trough-separator, although the same arrangement may be used in any other form of separator. A is a board forming the top of the trough, or a section thereof, and beneath is a plate, Z, of zinc or other material, screwed to it. This zinc is properly perforated for the insertion of the different sheaths S to correspond with the holes through the boardAfor the branches of the magnets, and by screwing it to the board all the sheaths are fastened in place, being held by their flanges between the two plane surfaces. They need not be fastened tightly; but by leaving a little freedom between the zinc and the wood they will be a little loose and free to conform to any accidental inequalities in the positions of the magnets which are to go into them. When one set of sheaths is worn through the Zinc plate can be taken off and a new set of'sheaths inserted in a very few moments; or single sheaths accidentally injured may be similarly replaced.

The sheaths may, if preferred, go through A, and the plate Z be placed on the flanges over A.

Fig.8 represents a section through one mag net, M, .with its sheaths S and the board A, which is removable from the magnets, and carries with it the sheaths and the iron gathered upon them. The same arrangement, ofcourse, extends across the width of the trough, one board, A, and plate Z answering for the whole gang of magnets. The magnets are firmly secured to a frame, B, which holds them in place, and to which the boardA is temporarily secured during use by an eye-catch or otherwise. The board A has ears or projections slidingin grooves in the frame B, causing it to carry the sheaths straight on and off the magnets. There are also slight grooves out in the edge of B to give the fingers a hold on the surface of A for removing it; or A may project out beyond the frame B for that purpose. Fig. 5 is a plan of a trough having five such gangs of six magnets each, with another gang of pseudoanagnets, a a, at the upper end.

The cover is represented as divided through the center at :0, so that the whole three upper gangs can be lifted off at once. The lower half of the cover is shown as divided into three sections, each containing one gang of magnets; but, of course, the whole cover can be so divided into sections, or it may be made entire, in which case one board, A, one plate,

IIO

Z, and one frame, B, would answer for the whole trough. The cover can be taken'off, turned bottom side up, and set back on the trough, or on any convenient support; but I prefer that the cover be made in sections, each section hinged at b b to the side of the trough, so that it can be swung over and suitably supported. The catches are then loosened and the board A lifted off, carrying the sheaths with their accumulated iron away from the magnets, when the iron ceases to be held, falls down loosely, and. can be dumped off into a box. The cleaned sheath-board is then replaced and secured and the cover-swung back over the trough ready for work. Thus the cleaning of the magnets can be done without stopping the flow of the grain. When not in use, the iron may be left on to act as keepers, or the ordinary keepers may be put on outside of the sheaths to preserve the power of the magnets.

The frame-work supporting the trough is not shown in the figures, being unnecessary, as any suitable frame may be used; or my invention may be constructed as a cover and be applied to any trough, spout, or other conveyer already built and in use.

The cover or the whole trough may be constructed, supported, and moved in other ways without departing from the principle of my invention. For example, the cover or top of the trough may revolve on axles or pivots at or near the center of the whole mass of magnets, &c., to bring the sheaths uppermost and permit of their ready removal; or the magnets, sheaths, &c., may be fixed in the bottom of the trough instead of the top, and the whole gang of magnets arranged to be lowered out of the sheaths and raised up into them again; or the whole trough, sheaths, and all may be lifted. off the magnet fixed to the frame-work to discharge the iron, and then be replaced; or any other suitable arrangements may be adopted for separating the magnets and sheaths at the proper times and discharging the iron; but I consider the method shown and described as the best for a trough-separator.

When my invention is applied to a revolving cylinder I prefer to employ theinterior for the working-surface. The cylinder is made of any suitable material, size, or proportions, and revolved on hollow journals, friction-rollers, or any other suitable contrivances which willadmitoflargeinlet and outlet pipes or troughs, and leave the ends, or at least the lower end, very open, so that the cleaned grain can roll out of thelower end freely as the cylinderrevolves, as described in my former Patent No. 223,901. I can use in this form of separator electro'ortemporary or induced magnets, as described in that patent; but my invention is especially useful with permanent magnets. These I attach to the cylinder in any manner preferred, and arrange the diaphragms or sheaths in sections or parts, each of which may be removed from its magnets independently as it comes over the trough L, Fig. 9, in the interior of the cylinder E, and so discharge theironinto the trough, whence'it may escape through an outlet-pipe, as described in that patent. Ordinarily from four to six sections will be sufficient, although either more or less may be used.

The sheaths may be formed in shallow steps, each step fitting one side and the end of alongitudinal row of magnets arranged as at the right half of Fig. 1.. The object and effect are that the iron is attracted more and more strongly as it slides down toward the ends of the magnets. Should the rush of grain carry the iron along the surface of the diaphragm and over the corner of the step, it would cling to it till carried under the lee of the step and opposite the ends of the magnets, where it would remain, being comparatively protected from the force of the grain. To prevent as much as possible the iron being swept along by the grain, I would either pass the sheath between rollers which will roll grooves into the outer surface, or corrugate it very slightly longitudinally, not enough to stop the wheat, but merely give the pieces of iron a hold or restingplace. The rolling is preferable, as it leaves the higher parts or ridges, upon which the principal part of the wear comes, of the greatest thickness, while if simply corrugated the tops of the ridges would wear through before the hollows were weakened. The edges of the sections of the sheath must extend out far enough beyond the magnets to prevent particles of iron getting under them and on the magnets. Of course, the sheath-sections can be perfectly. circular in form, or lie flatly upon the soft-metal strips or pieces shown in my former patent referred to.

Instead of step-sheaths the magnets may pointin ward and a system of individual sheaths be used with them, as before described and shown in Fig. 8, each section of the diaphragm or interior casing of the cylinder carrying its proportionate number of sheaths. These sections may slide inward and outward parallel with the lengths of the sheaths, or they may be pivoted at one side, in which case the branches of the magnets can be formed in curves corresponding to the circular are described by the sheaths at that distance from the pivot. This will be understood by referring to the curved magnet shown in Fig. 4. The individual sheaths, whatever their particular forms, may have their greatest widths arranged either circularly or spirally, so that as the grain rolls down from the rising side of the cylinder it will flow between these projecting sheaths and be caught in the same way as before described with the trough form.

Instead of individual sheaths thus attached to the sections of the lining, the lining may be made of longitudinal strips of material, corrugated crosswise, to reach around the suc cessive magnets, as if in Fig.8 one strip of metal reached from one side of the trough to the other, being formed to fit closely to each of the magnets, then the ends of the furrows or troughs thus made being properly closed up and the strip properly secured to the section of the lining. Many other arrangements may be used to suit the requirements of particular cases.

The lining or coating of the cylinder, as be fore stated, is divided into any convenient number of longitudinal sections, and each may cover one, two, three, or more longitudinal rows of magnetsiu this case two, as before described. Fig. 9 shows how these sections may be removed from the magnets. Each section G has a stiff and substantial frame-work I 5 carrying the diaphragm or sheaths, with a lever or arm, H, at each end and on the rear side of the frame, pivoted at h to some part of the cylinder, which may be one of the spokes. To each section is also fixed a projecting rod, J, so curved that as it comes under the grooved roller K by the revolution of the cylinder the section will be forced down into the position shown by the dotted lines, thus carrying the iron away from the magnets, so that it drops off into the trough L. The curvature of the rod J then allows the section G to return to its place again, being pressed upward by springs, and kept up by them except when forced down by roller K, which may be carried by any convenient stationary part near the cylinder. By adjusting this roller higher or lower the sections which successively come under it are forced down less or farther from the magnets, as required 5 or, when necessary, it can be raised far enough to leave the sections undisturbed to accumulate iron upon them to act as keepers for the magnets when not in use.

There are numberless other ways of applyin g my invention to either an internal or external cylinder, trough, or other conveyer for the material to be separated; in the forms, materials, and constructions of the diaphragms or sheaths, their application to the magnets, the modes of combining the magnets and the diaphragms or sheaths with the different parts of the conveyer, and of manipulating eitheror both to produce the desired effects; but I have already explained it sufficiently to enable any one versed in the art to apply and use it successfully in any case.

Having thus described my invention, I hereby reserve as subject of future application all matters not expressly claimed herein.

What I claim as new, and desire to secure by Letters Patent, is-

1. A sheath or easin g for a magnet in a sepa rating apparatus, fitting around two or more of the attracting-surfaces thereof and protecting them from contact with the material to be 60 operated upon, while utilizing their attractive powers through it, and adapted to be readily removed from the magnets and replaced thereon.

2. A sheath or casin g for the magnet or magnets, constructed to prevent contact of the iron with the sides of the magnets, while utilizing one or more of the sides for separating purposes.

3. A separable sheath or casin g for the magnet or magnets of a separating apparatus, which prevents contact of the iron with the magnet or magnets, while utilizing their attractive power through it on two or more of their surfaces.

4. An individual sheaththat is to say, a sheath for each magnet or each leg of a mag net--to protect the attracting-surfaces from contact with the material to be operated upon, while utilizing theirattracti ve powers through it for separating purposes, and adapted to be readily removed from the magnet and replaced thereon.

5. In magnetic separating apparatus, the combination of a magnet, a magnetic metal diaphragm or sheath, and a non-magnetic substance between them, substantially as and for the purposes set forth.

6. In magnetic separating apparatus, a diaphragm or sheath composed of soft iron or steel, plated or coated on one or both sides with tin, zinc, or other non-magnetic metal or substance.

7. In magnetic separating apparatus, the method of separating magnetized metal fragments from grain, &c., by means of their own attraction for unmagnetized bars or pieces of soft iron or other magnetic metal, substan tially as set forth.

8. In magnetic separating apparatus, the construction of the conveyer in movable or separable parts or sections, one or more parts containing magnets, while one or more other parts contain diaphragms or sheaths for the magnets, the two classes of parts being adjustable together to attract and seize the iron while in or near the grain, and separable when out of the grain to carry the iron thus gathered away from the magnets and discharge it separately from the grain.

9. The combination, with a trough or other conveyer having magnets suitably arranged for separating iron from grain, of a diaphragm or sheath arranged in sections or parts, one or more of which may be moved at the proper times to carry the iron gathered by the magnet or magnets behind them away from the magnets and discharge it.

CHARLES E. FRITZ.

In presence of- GEO. KIRKLAND, SEYMOUR Sco'r'r. 

